Tennis racket press



Sept. 24, 1968 G. MAXON, JR 3,402,931

TENNIS RACKET PRESS Filed A ril 26, 1965 United States Patent() 3,402,931 TENNIS RACKET PRESS Glenway Maxon, Jr., 1830 E. Kane Place, Milwaukee, Wis. 53202 Filed Apr. 26, 1965, Ser. No. 450,740 2 Claims. (Cl. 27374) ABSTRACT OF THE DISCLOSURE A- press base member of tubular material, for rigidity, having an elliptical shape corresponding to that of a racket frame, has opposite surfaces that define parallel planes and either or both of which can be overlain by a racket frame. A clamping bar overiles a racket frame on the press base member, and screws through its ends are engageable in lugs on opposite sides of the base member that are on a line parallel to its minor axis and intermediate the minor axis and one end of the base member.

This invention relates to tennis racket presses and refers more particularly to apparatus for straightening the frame of a tennis racket when the same is warped, bowed or twisted out of the desired flatness.

The oval or elliptical frame of a tennis racket is strung with gut or nylon strings that are under substantial tension; and hence if any portion of the frame warps or bows out of coplanar relationship with the remainder thereof, the tension of the strings tends to aggravate the warping or bowing. Initially, warping or bowing may result from the effects upon the wooden racket frame of changes in air temperature and humidity, or improper stringing. Any deformation of a racket frame from true flatness is obviously undesirable because it detracts from the accuracy with which a ball can be directed when struck by the racket.

Heretofore there have been proposed a number of presses for straightening warped or bowed tennis racket frames, but all of these have possessed certain defects and disadvantages. In contrast to prior devices of this type, it is an object of the present invention to provide a tennis racket press which is inexpensive, rugged and simple in construction and operation, and which, moreover, provides means for achieving a very eflicient and acurate straightening of a warped or bowed tennis racket frame.

Another object of this invention is to provide a simple and inexpensive press base member having an oval or elliptical loop shape, substantially corresponding to that of the tennis racket frame, and having axially opposite coplanar surfaces against either of which the racket frame is adapted to be fiatwise clamped, which press base member is sufficiently rigid so that it cannot be twisted to appreciably deform its surface out of coplanar relationship, even when substantial twisting loads are imposed upon it as during straightening of a tennis racket frame.

Still another object of this invention is to provide a racket press which can be clampingly engaged with selected spaced apart portions of a tennis racket frame in such a manner that a corrective bow or warp can be applied to the frame, opposite to any existing bow or warp therein, by which the frame can be restored to true flatness.

With the above and other objects in view which will appear as the description proceeds, this invention resides in the novel construction, combination and arrangement of par-ts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the herein-disclosed invention may be made as come within the scope of the claims.

The accompanying drawing illustrates one complete ex- 3,402,931 Patented Sept. 24, 1968 ample of the physical embodiment of the invention constructed according to the best mode so far devised for the practical application of the principles thereof, and in which:

FIGURE 1 is a perspective view of the tennis racket press of this invention with its parts shown in disassembled relation to one another;

FIGURE 2 is a top plan view of the racket press with a tennis racket in place therein;

FIGURE 3 is a side view of the racket press assembled with a pair of tennis rackets, one of which has been preliminarily set in place in the press, unclamped, and the other of which is clamped in the press; and

FIGURE 4 is a cross-sectional view on an enlarged scale, taken on the plane of the line 4-4 in FIGURE 1.

Referring now to the accompanying drawings, the tennis racket press of this invention comprises, as best seen in FIGURE 1, a loop-like generally elliptical or oval press base member 5 having radially outwardly projecting lugs 6 at opposite sides thereof, a pair of clamping bars 7 and 8, and bolts 9 which are adapted to extend through the end portions of the clamping bars and into threaded holes 10 in the lugs 6.

The oval or elliptical press base member 5 corresponds generally to the size and shape of the frame portion 12 of a tennis racket 13. To insure that the press base member will have sufficient rigidity to resist deformation out of flatness under substantially large twisting and bending forces, it can be made of tubular metal and preferably has a rectangular cross section so as to have axially opposite coplanar surfaces.

The lugs 6 are welded or otherwise suitably secured to the radially outer surface of the base member, and each is preferably provided with two threaded holes 10. The lugs are spaced a small distance to one side of the minor axis of the press base member 5, .and are on a line parallel thereto.

The clamping bars 7 and 8 can be either tubular or made of solid bar stock. Each is of such length that it can span the press base member with its end portions overlying the opposite lugs 6. Two clamping bars are provided so that the press can be used with two tennis rackets at once, as illustrated in FIGURE 3, although it will be understood that only one clamping bar is needed if there is no occasion for accommodating more than one racket at a time, and in that event each of the lugs 6 would need to have only one threaded hole.

Installation of a tennis racket in the press of this invention is extremely simple. The screws 9, received in the clamping bars 7 and 8 as illustrated in FIGURE 1, have their tip portions engaged in the lugs 6, so that the head portion of a racket frame can readily be inserted edgewise forwardly between one of the clamping bars and the elliptical press base member 5, from either end of the latter. The fiat axially opposite surfaces of the base member provide a reference plane by which the head of the racket can be visually checked for bowing and twisting. If the racket head is true and flat, the screws 9 can be turned into the lugs until the clamping bar exerts only a light clamping force upon the racket head, to lightly clamp it against the press base member.

When the racket head is warped or bowed out of flatness, such bowing will usually be along the major axis of the head portion of the frame, and in that case the racket is inserted into the press with the bow or warp so oriented that the minor axis portion of the racket frame is spaced from the adjacent axial surface of the press base member, as with the upper racket in FIGURE 3. A spacer element 15 is inserted between the racket frame and the press base member, near the tip of the racket, at the point where the racket frame contacts the press member. The screws 9 are then tightened so that the clamping bar imposes substantial force upon the racket head, bowing it in the manner illustrated by the lower racket in FIGURE 3, to impart a curvature or bow to the racket which is directly opposite to the undesired warp or bow therein.

If the bow should be along the minor axis of the racket head, the racket is so placed in the press that portions of the racket frame along the major axis thereof are in contact with the press base member at said points, near the handle and near the tip of the racket, to impart an opposite bow to it. It will be apparent that any type of warp, twist or bow in a racket can be corrected by proper location of a spacer element or spacer elements.

After the racket has been kept in the press for some time the screws 9 are released to relax all clamping force, and the racket is inspected to determine whether it has been trued. If it still has some warp or twist, the screws are again tightened to continue the straightening treatment for a further interval, readjusting the spacer element or elements if necessary. After flatness has been achieved, the racket may be stored in the press with only a slight corrective bow to prevent return of the warped condition.

The spacer elements can be of any suitable shape, size and material, although rubber or a similar resilient material is preferred, in order to avoid the possibility of damage to the racket frame as the same is forced against the spacer elements by the clamping bar. Preferably the press base member is made of magnetically permeable metal and the spacer elements are made of magnetic rubber (i.e., rubber having magnetized metal powder embedded therein) so that the spacer elements tend to adhere magnetically to the press base member and hold any position in which they may be placed.

From the foregoing description taken together with the accompanying drawing it will be apparent that this invention provides a very simple and inexpensive but very easily used, accurate and reliable press for straightening tennis rackets.

What is claimed as my invention is:

1. A press for straightening tennis rackets, comprising:

(A) a metal press base member of substantially rigid tubular material having a substantially elliptical shape and size generally corresponding to that of a tennis racket frame and having opposite surfaces that define substantially parallel planes;

(B) a bar long enough to span the head portion of a tennis racket frame along a line parallel to the minor axis; 7

(C) a pair of opposite, radially outwardly projecting lugs on the press base member, one at each side thereof, lying on a line substantially parallel to the minor axis of the press base member and intermediate said minor axis and one end of the press base member;

(D) screw means engaged in the end portions of said bar and in said lugs, for drawing the bar flatwise toward one axial surface of the press base member to clampingly confine the frame of a racket thereagainst; and

(E) spacer means insertable between the press base member and the frame of a racket clamped thereto, at a location spaced from the clamping means, for imparting to the racket frame a corrective bowing away from the plane of its adjacent surface of the press base member.

2. The racket press of claim 1, further characterized by the following:

(A) the press base member is made of magnetically permeable metal; and

(B) said spacer means is magnetic, so as to be capable of adhering to the press base member at any location thereon, and comprises a body of substantially soft, resilient material so that it will not dent a racket frame engaged therewith under clamping force.

References Cited UNITED STATES PATENTS 978,455 12/1910 Johnson 1 27374 1,558,281 10/ 1925 Potts 273-74 1,883,030 10/1932 Smith 273-74 FOREIGN PATENTS 949 1903 Great Britain.

198,626 6/1923 Great Britain.

247,775 2/ 1926 Great Britain.

616,912 1/1949 Great Britain.

ANTON O. OECHSLE, Primary Examiner.

R. J. APLEY, Assistant Examiner. 

